google_ai: Remove unused `extract_text_from_events` function (#28723)

This PR removes the `extract_text_from_events` function from
`google_ai`, as it was not used anywhere.

Release Notes:

- N/A
a8b1ef3531Marshall Bowers committed on 4/14/2025, 10:01:21 PM· committed by GitHubparentc8ccc47
1 file changedLine totals unavailable